From patchwork Mon Sep 7 13:15:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joerg Roedel X-Patchwork-Id: 11761753 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 559EB746 for ; Mon, 7 Sep 2020 17:37:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 472C0208C7 for ; Mon, 7 Sep 2020 17:37:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729663AbgIGRga (ORCPT ); Mon, 7 Sep 2020 13:36:30 -0400 Received: from 8bytes.org ([81.169.241.247]:43658 "EHLO theia.8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729476AbgIGNSQ (ORCPT ); Mon, 7 Sep 2020 09:18:16 -0400 Received: from cap.home.8bytes.org (p549add56.dip0.t-ipconnect.de [84.154.221.86]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by theia.8bytes.org (Postfix) with ESMTPSA id 5B5F5F13; Mon, 7 Sep 2020 15:16:51 +0200 (CEST) From: Joerg Roedel To: x86@kernel.org Cc: Joerg Roedel , Joerg Roedel , Kees Cook , hpa@zytor.com, Andy Lutomirski , Dave Hansen , Peter Zijlstra , Jiri Slaby , Dan Williams , Tom Lendacky , Juergen Gross , David Rientjes , Cfir Cohen , Erdem Aktas , Masami Hiramatsu , Mike Stunes , Sean Christopherson , Martin Radev , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org Subject: [PATCH v7 18/72] x86/boot/compressed/64: Change add_identity_map() to take start and end Date: Mon, 7 Sep 2020 15:15:19 +0200 Message-Id: <20200907131613.12703-19-joro@8bytes.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200907131613.12703-1-joro@8bytes.org> References: <20200907131613.12703-1-joro@8bytes.org> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org From: Joerg Roedel Changing the function to take start and end as parameters instead of start and size simplifies the callers, which don't need to calculate the size if they already have start and end. Signed-off-by: Joerg Roedel Reviewed-by: Kees Cook --- arch/x86/boot/compressed/ident_map_64.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/arch/x86/boot/compressed/ident_map_64.c b/arch/x86/boot/compressed/ident_map_64.c index c63257bf8373..62e42c11a336 100644 --- a/arch/x86/boot/compressed/ident_map_64.c +++ b/arch/x86/boot/compressed/ident_map_64.c @@ -89,10 +89,8 @@ static struct x86_mapping_info mapping_info; /* * Adds the specified range to the identity mappings. */ -static void add_identity_map(unsigned long start, unsigned long size) +static void add_identity_map(unsigned long start, unsigned long end) { - unsigned long end = start + size; - /* Align boundary to 2M. */ start = round_down(start, PMD_SIZE); end = round_up(end, PMD_SIZE); @@ -107,8 +105,6 @@ static void add_identity_map(unsigned long start, unsigned long size) /* Locates and clears a region for a new top level page table. */ void initialize_identity_maps(void) { - unsigned long start, size; - /* If running as an SEV guest, the encryption mask is required. */ set_sev_encryption_mask(); @@ -155,9 +151,7 @@ void initialize_identity_maps(void) * New page-table is set up - map the kernel image and load it * into cr3. */ - start = (unsigned long)_head; - size = _end - _head; - add_identity_map(start, size); + add_identity_map((unsigned long)_head, (unsigned long)_end); write_cr3(top_level_pgt); } @@ -189,7 +183,8 @@ static void do_pf_error(const char *msg, unsigned long error_code, void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code) { - unsigned long address = native_read_cr2(); + unsigned long address = native_read_cr2() & PMD_MASK; + unsigned long end = address + PMD_SIZE; /* * Check for unexpected error codes. Unexpected are: @@ -204,5 +199,5 @@ void do_boot_page_fault(struct pt_regs *regs, unsigned long error_code) * Error code is sane - now identity map the 2M region around * the faulting address. */ - add_identity_map(address & PMD_MASK, PMD_SIZE); + add_identity_map(address, end); }